Two cAMP signaling compartments centered on adenylyl cyclase (AC) exist in human airway smooth muscle (HASM) cells, one containing β-adrenergic receptor AC6 and another containing E prostanoid receptor AC2. We hypothesized that different PDE isozymes selectively regulate cAMP signaling in each compartment. According to RNA-sequencing data, 18 of 24 PDE genes were expressed in primary HASM cells derived from age- and sex-matched donors with and without asthma. PDE8A was the third most abundant of the cAMP-degrading PDE genes, after PDE4A and PDE1A. Knockdown of PDE8A using shRNA evoked twofold greater cAMP responses to 1 μM forskolin in the presence of 3-isobutyl-1-methylxanthine. Overexpression of AC2 did not alter this response, but overexpression of AC6 increased cAMP responses an additional 80%. We examined cAMP dynamics in live HASM cells using a fluorescence sensor. PF-04957325, a PDE8-selective inhibitor, increased basal cAMP concentrations by itself, indicating a significant basal level of cAMP synthesis. In the presence of an AC inhibitor to reduce basal signaling, PF-04957325 accelerated cAMP production and increased the inhibition of cell proliferation induced by isoproterenol, but it had no effect on cAMP concentrations or cell proliferation regulated by prostaglandin E. Lipid raft fractionation of HASM cells revealed PDE8A immunoreactivity in buoyant fractions containing caveolin-1 and AC5/6 immunoreactivity. Thus, PDE8 is expressed in lipid rafts of HASM cells, where it specifically regulates β-adrenergic receptor AC6 signaling without effects on signaling by the E prostanoid receptors 2/4-AC2 complex. In airway diseases such as asthma and chronic obstructive pulmonary disease, PDE8 may represent a novel therapeutic target to modulate HASM responsiveness and airway remodeling.

Trait databases have become important resources for large-scale comparative studies in ecology and evolution. Here we introduce the AnimalTraits database, a curated database of body mass, metabolic rate and brain size, in standardised units, for terrestrial animals. The database has broad taxonomic breadth, including tetrapods, arthropods, molluscs and annelids from almost 2000 species and 1000 genera. All data recorded in the database are sourced from their original empirical publication, and the original metrics and measurements are included with each record. This allows for subsequent data transformations as required. We have included rich metadata to allow users to filter the dataset. The additional R scripts we provide will assist researchers with aggregating standardised observations into species-level trait values. Our goals are to provide this resource without restrictions, to keep the AnimalTraits database current, and to grow the number of relevant traits in the future.

Although BCL-xL is critical to the survival of mature erythrocytes, it is still unclear whether other antiapoptotic molecules mediate survival during earlier stages of erythropoiesis. Here, we demonstrate that erythroid-specific Mcl1 deletion results in embryonic lethality beyond embryonic day 13.5 as a result of severe anemia caused by a lack of mature red blood cells (RBCs). Mcl1-deleted embryos exhibit stunted growth, ischemic necrosis, and decreased RBCs in the blood. Furthermore, we demonstrate that MCL-1 is only required during early definitive erythropoiesis; during later stages, developing erythrocytes become MCL-1 independent and upregulate the expression of BCL-xL. Functionally, MCL-1 relies upon its ability to prevent apoptosis to promote erythroid development because codeletion of the proapoptotic effectors Bax and Bak can overcome the requirement for MCL-1 expression. Furthermore, ectopic expression of human BCL2 in erythroid progenitors can compensate for Mcl1 deletion, indicating redundancy between these 2 antiapoptotic family members. These data clearly demonstrate a requirement for MCL-1 in promoting survival of early erythroid progenitors.

Antiapoptotic MCL1 is one of the most frequently amplified genes in human cancers and elevated expression confers resistance to many therapeutics including the BH3-mimetic agents ABT-199 and ABT-263. The antimalarial, dihydroartemisinin (DHA) translationally represses MCL-1 and synergizes with BH3-mimetics. To explore how DHA represses MCL-1, a genome-wide CRISPR screen identified that loss of genes in the heme synthesis pathway renders mouse BCR-ABL+ B-ALL cells resistant to DHA-induced death. Mechanistically, DHA disrupts the interaction between heme and the eIF2α kinase heme-regulated inhibitor (HRI) triggering the integrated stress response. Genetic ablation of Eif2ak1, which encodes HRI, blocks MCL-1 repression in response to DHA treatment and represses the synergistic killing of DHA and BH3-mimetics compared with wild-type leukemia. Furthermore, BTdCPU, a small-molecule activator of HRI, similarly triggers MCL-1 repression and synergizes with BH3-mimetics in mouse and human leukemia including both Ph+ and Ph-like B-ALL. Finally, combinatorial treatment of leukemia bearing mice with both BTdCPU and a BH3-mimetic extended survival and repressed MCL-1 in vivo. These findings reveal for the first time that the HRI-dependent cellular heme-sensing pathway can modulate apoptosis in leukemic cells by repressing MCL-1 and increasing their responsiveness to BH3-mimetics. This signaling pathway could represent a generalizable mechanism for repressing MCL-1 expression in malignant cells and sensitizing them to available therapeutics. Implications: The HRI-dependent cellular heme-sensing pathway can modulate apoptotic sensitivity in leukemic cells by repressing antiapoptotic MCL-1 and increasing their responsiveness to BH3-mimetics.

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Purpose The current research study investigates the speech therapy experiences of an individual who covertly stuttered for approximately 40 years; at the time of the interview, she was in her mid-40s. Method The single-case study is a qualitative thematic analysis of the speech therapy experiences of one individual across her life span. In addition to her stuttering, the participant lives with a significant primary diagnosis that she has had since birth, which impacts her activities in daily living. Interview questions were open-ended and conducted via Skype. The interview was transcribed, and a thematic analysis of the recorded transcripts was conducted to investigate her experiences in speech therapy as an individual who covertly stutters. Findings The current findings reveal five major themes regarding the speech therapy experiences of an individual who covertly stutters: (a) nonindividualized treatment and goals, (b) blaming and shaming associated with speech therapy and stuttering, (c) positive self-regard during speech therapy attendance, (d) the use of avoidance strategies and relation to speech therapy, and (e) the evolution of therapy goals. Direct quotations from the participant are used to support these themes. Discussion The significant impact of covert stuttering on an individual is discussed. Results from the participant's experiences indicate an essential need to conduct individualized speech therapy for people who stutter. Speech-language pathologists and others working with persons who stutter maintain a responsibility to recognize the role that case history and counseling play in order to appropriately serve people who covertly stutter.

Mature erythrocytes are under tight homeostatic control with the need for constant replacement from progenitors to replace damaged or obsolete red blood cells (RBCs). This process is regulated largely by erythropoietin (Epo) which promotes the survival of erythroid progenitors and facilitates their differentiation and proliferation. Ablation of Bcl2l1 (which encodes BCL-xL) results in embryonic lethality with a lack of mature erythrocytes but does not perturb erythroid progenitors. Similarly, conditional Bcl2l1deletion results in severe anemia with the death of late erythroid progenitors and induction of extramedullary erythropoiesis. While BCL-xL is critical to the survival of mature erythrocytes, it is still unclear whether other anti-apoptotic molecules mediate survival during earlier stages of erythropoiesis. Here, we demonstrate that erythroid-specific Mcl1deletion results in embryonic lethality due to severe anemia caused by a lack of mature RBCs. Mcl1-deleted embryos exhibit stunted growth, ischemic necrosis, and decreased RBCs in the blood. Furthermore, we demonstrate that the dependence on MCL-1 is only during early erythropoiesis, whereas during later stages the cells become MCL-1independent and upregulate the expression of BCL-xL. Functionally, MCL-1 relies upon its ability to prevent apoptosis to promote erythroid development since co-deletion of the pro-apoptotic effectors Bax and Bak can overcome the requirement for MCL-1 expression.Furthermore, ectopic expression of human BCL2 in erythroid progenitors can compensate for Mcl1 deletion, indicating redundancy between these two anti-apoptotic family members. These data clearly demonstrate a requirement for MCL-1 in promoting survival of early erythroid progenitors. Requirement for MCL-1 in Early ErythropoiesisRequirement for MCL-1 in Early Erythropoiesis 4 of individual anti-apoptotic molecules during hematopoiesis. Bcl2-deficient mice are viable, but exhibit a spectrum of abnormalities including lymphocyte apoptosis, but otherwise hematopoiesis proceeds unperturbed [13][14][15] . Loss of all three isoforms of Bcl2a1 causes only minor defects in hematopoiesis 16 . BCL-w is not required for hematopoiesis [17][18][19] . BCL-xL is required for late erythropoiesis and protection of mature platelets 10,20,21 . In contrast, Mcl1 is essential for survival of multiple hematopoietic lineages including stem cells 22 , B cells 23-25 , T cells 23,26,27 and neutrophils 28,29 . However, whether Mcl1 plays any role in erythropoiesis is unknown. Here, we report for the first time that conditional Mcl1-deletion, using an erythroidspecific mouse which contains the GFPcre gene knocked-in to the Epo receptor (EpoR) locus 30 , leads to failure of RBC maturation, anemia, and embryonic lethality. Using an ex vivo culture system, we show that expression of MCL-1 is only required during early erythropoiesis, but is dispensable later. Finally, Bax-and Bak-deletion, or lentiviralmediated overexpression of the pro-survival factor BCL2 can rescue Mcl1 loss in murine erythropoiesis...

<p>Stress pathways in cellular response to DHA</p>